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by turdnagel 1433 days ago
This kind of stuff is really awe-inspiring. I have a couple of questions for anyone who is knowledgeable on the subject:

1. Looking at the light from the tiny red-shifted galaxies that are ~13 billion years old... would the Milky Way appear the same to an observer ~13 billion ly from us?

2. What is the cause of the star pointed artifacts (specifically, having 6 major "points") for particularly bright objects? If you zoom in closely on any one of the points, you can almost make out a hex grid, as if the shape of the telescope's mirrors is the cause. Is that correct?

3 comments

1. Yes pretty much.

2. Yes the artifact shape is related to the mirror shape, and the support arms which block some light. this is called a Diffraction spike. There are a bunch of fake web telescope image videos on YouTube with 4pointed diffraction spikes so you can tell they are taken from a different telescope.

https://en.wikipedia.org/wiki/Diffraction_spike

on 1., I'm not sure but I'd guess so, yes.

on 2., you are seeing Diffraction Spikes[0] which are artefacts of the telescope's design.

[0]: https://en.wikipedia.org/wiki/Diffraction_spike

The points are caused by the support arms of the secondary mirror.